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Gargiulo and colleagues' meta-analysis compares transcatheter aortic valve implantation (TAVI) with surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis at low to intermediate and high risk (1). They conclude that early and midterm all-cause mortality were similar between TAVI and SAVR but that TAVI was associated with a statistically nonsignificant increased risk for long-term mortality. The authors' conclusion on long-term mortality was questionable because the overall result was driven mainly by data from observational studies, which caused significant heterogeneity and showed significant subgroup interaction between randomized trials and observational studies. Although all included observational studies were matched, residual confounding that cannot be removed without a randomized design still exists. Therefore, analyses should be separately performed and conclusions separately made. Furthermore, in the analyses of patients at low to intermediate risk, the authors did not perform separate analyses for randomized trials and observational studies. These results should be interpreted with caution.